This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This is a randomized, placebo-controlled, prevention-type clinical trial supported by the National Institute on Aging for a four-year period of exposure in which women 65 years and older who have a positive family history of dementia are given premarin/prempro (based on uterine status) versus placebo in an effort to prevent the occurence of Alzheimer's disease in a population that is vulnerable by family history. Our current enrollment in the trial is 28 women, and we are still actively enrolling. This trial is supported by an RO-1 to Dr. Mary Sano, who recently moved from Columbia to Mt. Sinai in New York. During the competitive renewal site visit, the RO-1 received a score of 159, and is confident that the funding will continue for another five years to support this ongoing work.